serval-dna/overlay_interface.c
2012-07-25 14:53:53 +09:30

1001 lines
30 KiB
C

/*
Serval Distributed Numbering Architecture (DNA)
Copyright (C) 2010 Paul Gardner-Stephen
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <assert.h>
#include <time.h>
#include "serval.h"
#include "strbuf.h"
#ifdef HAVE_IFADDRS_H
#include <ifaddrs.h>
#endif
int overlay_ready=0;
int overlay_interface_count=0;
overlay_interface overlay_interfaces[OVERLAY_MAX_INTERFACES];
int overlay_last_interface_number=-1;
struct interface_rules {
char *namespec;
unsigned long long speed_in_bits;
int port;
char type;
char excludeP;
struct interface_rules *next;
};
struct interface_rules *interface_filter=NULL;
struct profile_total interface_poll_stats;
struct profile_total dummy_poll_stats;
struct outgoing_packet{
overlay_interface *interface;
int i;
overlay_buffer *buffer;
};
struct sched_ent next_packet;
struct profile_total send_packet;
int overlay_tick_interface(int i, long long now);
unsigned char magic_header[]={/* Magic */ 'O',0x10,
/* Version */ 0x00,0x01};
/* Return milliseconds since server started. First call will always return zero.
Must use long long, not time_t, as time_t can be 32bits, which is too small for
milli-seconds since 1970. */
long long overlay_sequence_start_time = 0;
long long overlay_gettime_ms()
{
long long now;
if (!overlay_sequence_start_time) {
overlay_sequence_start_time = gettime_ms();
now = 0;
} else
now= gettime_ms()-overlay_sequence_start_time;
return now;
}
int overlay_interface_type(char *s)
{
if (!strcasecmp(s,"ethernet")) return OVERLAY_INTERFACE_ETHERNET;
if (!strcasecmp(s,"wifi")) return OVERLAY_INTERFACE_WIFI;
if (!strcasecmp(s,"other")) return OVERLAY_INTERFACE_UNKNOWN;
if (!strcasecmp(s,"catear")) return OVERLAY_INTERFACE_PACKETRADIO;
return WHY("Invalid interface type -- consider using 'wifi','ethernet' or 'other'");
}
int overlay_interface_arg(char *arg)
{
/* Parse an interface argument, of the form:
<+|->[interfacename][=type]
+interface tells DNA to sit on that interface
-interface tells DNA to not sit on that interface
+/- without an interface tells DNA to sit on all interfaces.
The first match rules, so -en0+ tells DNA to use all interfaces, excepting en0
The optional =type specifier tells DNA how to handle the interface in terms of
bandwidth:distance relationship for calculating tick times etc.
The special type =custom allows full specification:
XXX - Settle the custom specification now that we have changed the interface
management.
*/
char sign[80]="+";
char interface_name[80]="";
char speed[80]="1m";
char typestring[80]="wifi";
int port=PORT_DNA;
int type=OVERLAY_INTERFACE_UNKNOWN;
int n=0;
/* Too long */
if (strlen(arg)>79) return WHY("interface specification was >79 characters");
struct interface_rules *r=calloc(sizeof(struct interface_rules),1);
if (!r) return WHY("calloc(struct interface rules),1) failed");
if (sscanf(arg,"%[+-]%n%[^=:,]%n=%[^:]%n:%d%n:%[^:]%n",
sign,&n,interface_name,&n,typestring,&n,&port,&n,speed,&n)>=1)
{
if (n<strlen(arg)) { free(r); return WHY("Extra junk at end of interface specification"); }
if (strlen(sign)>1) { free(r); return WHY("Sign must be + or -"); }
switch(sign[0])
{
case '+': break;
case '-': r->excludeP=1; break;
default:
free(r);
return WHY("Invalid interface list item: Must begin with + or -");
}
long long speed_in_bits=parse_quantity(speed);
if (speed_in_bits<=1) {
free(r);
return WHY("Interfaces must be capable of at least 1 bit per second");
}
if (n<strlen(arg)) return WHY("Extra stuff at end of interface specification");
type=overlay_interface_type(typestring);
if (type<0) { free(r); return WHY("Invalid interface type in specification"); }
/* Okay, register the interface preference */
r->namespec=strdup(interface_name);
r->speed_in_bits=speed_in_bits;
r->port=port;
r->type=type;
r->next=interface_filter;
interface_filter=r;
return 0;
}
else { free(r); return WHY("Bad interface specification"); }
}
int overlay_interface_args(const char *arg)
{
/* Parse series of comma-separated interface definitions from a single argument
*/
int i=0;
char interface[80];
int len=0;
for(i=0;arg[i];i++)
{
if (arg[i]==','||arg[i]=='\n') {
interface[len]=0;
if (overlay_interface_arg(interface)) return WHY("Could not add interface");
len=0;
} else {
if (len<79) {
interface[len++]=arg[i];
interface[len]=0;
} else
return WHY("Interface definition is too long (each must be <80 characters)");
}
}
if (len) if (overlay_interface_arg(interface)) return WHY("Could not add final interface");
return 0;
}
int
overlay_interface_init_socket(int interface, struct sockaddr_in *src_addr, struct sockaddr_in *broadcast) {
char srctxt[INET_ADDRSTRLEN];
#define I(X) overlay_interfaces[interface].X
bcopy(broadcast, &I(broadcast_address), sizeof(struct sockaddr_in));
I(fileP) = 0;
I(alarm.poll.fd) = socket(PF_INET,SOCK_DGRAM,0);
if (I(alarm.poll.fd) < 0) {
WHY_perror("socket");
WHYF("Could not create UDP socket for interface: %s",strerror(errno));
goto error;
} else
INFOF("interface #%d fd=%d",interface, I(alarm.poll.fd));
int reuseP = 1;
if (setsockopt(I(alarm.poll.fd), SOL_SOCKET, SO_REUSEADDR, &reuseP, sizeof(reuseP)) < 0) {
WHY_perror("setsockopt(SO_REUSEADR)");
goto error;
}
#ifdef SO_REUSEPORT
if (setsockopt(I(alarm.poll.fd), SOL_SOCKET, SO_REUSEPORT, &reuseP, sizeof(reuseP)) < 0) {
WHY_perror("setsockopt(SO_REUSEPORT)");
goto error;
}
#endif
int broadcastP = 1;
if (setsockopt(I(alarm.poll.fd), SOL_SOCKET, SO_BROADCAST, &broadcastP, sizeof(broadcastP)) < 0) {
WHY_perror("setsockopt");
goto error;
}
/* Automatically close socket on calls to exec().
This makes life easier when we restart with an exec after receiving
a bad signal. */
fcntl(I(alarm.poll.fd), F_SETFL, fcntl(I(alarm.poll.fd), F_GETFL, NULL) | O_CLOEXEC);
/* @PGS/20120615
Use the broadcast address, so that we can reliably receive broadcast
traffic on all platforms. BUT on OSX we really need a non-broadcast socket
to send from, because you cannot send from a broadcast socket on OSX it seems.
*/
I(broadcast_address.sin_family) = AF_INET;
I(broadcast_address.sin_port) = htons(I(port));
if (bind(I(alarm.poll.fd), (const struct sockaddr *)&I(broadcast_address), sizeof(I(broadcast_address)))) {
WHY_perror("bind");
WHY("MP HLR server could not bind to requested UDP port (bind() failed)");
goto error;
}
assert(inet_ntop(AF_INET, (const void *)&I(broadcast_address.sin_addr), srctxt, INET_ADDRSTRLEN) != NULL);
if (debug & (DEBUG_PACKETRX | DEBUG_IO)) DEBUGF("Bound to %s:%d", srctxt, ntohs(I(broadcast_address.sin_port)));
I(alarm.poll.events)=POLLIN;
I(alarm.function) = overlay_interface_poll;
interface_poll_stats.name="overlay_interface_poll";
I(alarm.stats)=&interface_poll_stats;
watch(&I(alarm));
// run the first tick asap
I(alarm.alarm)=overlay_gettime_ms();
I(alarm.deadline)=I(alarm.alarm)+10;
schedule(&I(alarm));
return 0;
error:
close(I(alarm.poll.fd));
I(alarm.poll.fd)=-1;
return -1;
#undef I
}
int overlay_interface_init(char *name,struct sockaddr_in *src_addr,struct sockaddr_in *broadcast,
int speed_in_bits,int port,int type)
{
/* Too many interfaces */
if (overlay_interface_count>=OVERLAY_MAX_INTERFACES) return WHY("Too many interfaces -- Increase OVERLAY_MAX_INTERFACES");
#define I(X) overlay_interfaces[overlay_interface_count].X
strcpy(I(name),name);
/* Pick a reasonable default MTU.
This will ultimately get tuned by the bandwidth and other properties of the interface */
I(mtu)=1200;
I(observed)=1;
I(bits_per_second)=speed_in_bits;
I(port)=port;
I(type)=type;
I(last_tick_ms)=0;
I(alarm.poll.fd)=0;
switch (type) {
case OVERLAY_INTERFACE_PACKETRADIO:
I(tick_ms) = confValueGetInt64Range("mdp.packetradio.tick_ms", 15000LL, 1LL, 3600000LL);
break;
case OVERLAY_INTERFACE_ETHERNET:
I(tick_ms) = confValueGetInt64Range("mdp.ethernet.tick_ms", 500LL, 1LL, 3600000LL);
break;
case OVERLAY_INTERFACE_WIFI:
I(tick_ms) = confValueGetInt64Range("mdp.wifi.tick_ms", 500LL, 1LL, 3600000LL);
break;
case OVERLAY_INTERFACE_UNKNOWN:
I(tick_ms) = confValueGetInt64Range("mdp.unknown.tick_ms", 500LL, 1LL, 3600000LL);
break;
default:
return WHYF("Unsupported interface type %d", type);
}
if (name[0]=='>') {
I(fileP)=1;
char dummyfile[1024];
if (name[1]=='/') {
/* Absolute path */
snprintf(dummyfile,1024,"%s",&name[1]);
} else
/* Relative to instance path */
if (!FORM_SERVAL_INSTANCE_PATH(dummyfile, &name[1]))
return WHY("could not form dummy interfance name");
if ((I(alarm.poll.fd) = open(dummyfile,O_APPEND|O_RDWR)) < 1) {
return WHY("could not open dummy interface file for append");
}
/* Seek to end of file as initial reading point */
I(offset)=lseek(I(alarm.poll.fd),0,SEEK_END); /* socket gets reused to hold file offset */
/* XXX later add pretend location information so that we can decide which "packets" to receive
based on closeness */
// schedule an alarm for this interface
I(alarm.function)=overlay_dummy_poll;
I(alarm.alarm)=overlay_gettime_ms()+10;
I(alarm.deadline)=I(alarm.alarm);
dummy_poll_stats.name="overlay_dummy_poll";
I(alarm.stats)=&dummy_poll_stats;
schedule(&I(alarm));
} else {
if (overlay_interface_init_socket(overlay_interface_count,src_addr,broadcast))
return WHY("overlay_interface_init_socket() failed");
}
overlay_interface_count++;
#undef I
return 0;
}
void overlay_interface_poll(struct sched_ent *alarm)
{
struct overlay_interface *interface = (overlay_interface *)alarm;
int plen=0;
unsigned char packet[16384];
struct sockaddr src_addr;
socklen_t addrlen = sizeof(src_addr);
if (alarm->poll.revents==0){
// tick the interface
unsigned long long now = overlay_gettime_ms();
int i = (interface - overlay_interfaces);
overlay_tick_interface(i, now);
alarm->alarm=now+interface->tick_ms;
alarm->deadline=alarm->alarm+interface->tick_ms/2;
schedule(alarm);
return;
}
/* Read only one UDP packet per call to share resources more fairly, and also
enable stats to accurately count packets received */
int recvttl=1;
plen = recvwithttl(alarm->poll.fd,packet, sizeof(packet), &recvttl, &src_addr, &addrlen);
if (plen != -1) {
/* We have a frame from this interface */
if (debug&DEBUG_PACKETRX)
serval_packetvisualise(open_logging(),"Read from real interface", packet,plen);
if (debug&DEBUG_OVERLAYINTERFACES) DEBUGF("Received %d bytes on interface %s",plen,interface->name);
if (packetOk(interface,packet,plen,NULL,recvttl,&src_addr,addrlen,1)) {
WHY("Malformed packet");
// Do we really want to attempt to parse it again?
//serval_packetvisualise(open_logging(), "Malformed packet", packet,plen);
}
}
}
void overlay_dummy_poll(struct sched_ent *alarm)
{
overlay_interface *interface = (overlay_interface *)alarm;
/* Grab packets, unpackage and dispatch frames to consumers */
/* XXX Okay, so how are we managing out-of-process consumers?
They need some way to register their interest in listening to a port.
*/
unsigned char packet[16384];
int plen=0;
struct sockaddr src_addr;
size_t addrlen = sizeof(src_addr);
unsigned char transaction_id[8];
unsigned long long now = overlay_gettime_ms();
if (interface->last_tick_ms + interface->tick_ms <= now){
// tick the interface
int i = (interface - overlay_interfaces);
overlay_tick_interface(i, now);
}
/* Read from dummy interface file */
long long length=lseek(alarm->poll.fd,0,SEEK_END);
if (interface->offset>=length)
{
/* if there's no input, while we want to check for more soon,
we need to allow all other low priority alarms to fire first,
otherwise we'll dominate the scheduler without accomplishing anything */
alarm->alarm = overlay_gettime_ms()+20;
alarm->deadline = alarm->alarm + 10000;
if (alarm->alarm > interface->last_tick_ms + interface->tick_ms)
alarm->alarm = interface->last_tick_ms + interface->tick_ms;
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("At end of input on dummy interface %s", interface->name);
}
else
{
lseek(alarm->poll.fd,interface->offset,SEEK_SET);
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("Read interface %s (size=%lld) at offset=%d",interface->name, length, interface->offset);
ssize_t nread = read(alarm->poll.fd,&packet[0],2048);
if (nread == -1)
WHY_perror("read");
else {
interface->offset += nread;
if (nread == 2048) {
plen = packet[110]+(packet[111]<<8);
if (plen > nread - 128)
plen = -1;
if (debug&DEBUG_PACKETRX)
serval_packetvisualise(open_logging(), "Read from dummy interface", &packet[128], plen);
bzero(&transaction_id[0],8);
bzero(&src_addr,sizeof(src_addr));
if (plen >= 4) {
if (packet[0] == 0x01 && packet[1] == 0 && packet[2] == 0 && packet[3] == 0) {
if (packetOk(interface,&packet[128],plen,transaction_id, -1 /* fake TTL */, &src_addr,addrlen,1) == -1)
WARN("Unsupported packet from dummy interface");
} else {
WARNF("Unsupported packet version from dummy interface: %02x %02x %02x %02x", packet[0], packet[1], packet[2], packet[3]);
}
} else {
WARNF("Invalid packet from dummy interface: plen=%lld", (long long) plen);
}
}
else
WARNF("Read %lld bytes from dummy interface", nread);
}
/* keep reading new packets as fast as possible,
but don't prevent other high priority alarms */
alarm->alarm = overlay_gettime_ms();
alarm->deadline = alarm->alarm + 200;
}
schedule(alarm);
return ;
}
int overlay_broadcast_ensemble(int interface_number,
struct sockaddr_in *recipientaddr /* NULL == broadcast */,
unsigned char *bytes,int len)
{
struct sockaddr_in s;
if (debug&DEBUG_PACKETTX)
{
DEBUGF("Sending this packet via interface #%d",interface_number);
serval_packetvisualise(open_logging(),NULL,bytes,len);
}
overlay_interface *interface = &overlay_interfaces[interface_number];
memset(&s, '\0', sizeof(struct sockaddr_in));
if (recipientaddr) {
bcopy(recipientaddr,&s,sizeof(struct sockaddr_in));
}
else {
s = interface->broadcast_address;
s.sin_family = AF_INET;
if (debug&DEBUG_PACKETTX) DEBUGF("Port=%d",interface->port);
s.sin_port = htons(interface->port);
}
if (interface->fileP)
{
char buf[2048];
bzero(&buf[0],128);
/* Version information */
buf[0]=1; buf[1]=0;
buf[2]=0; buf[3]=0;
/* PID of creator */
buf[4]=getpid()&0xff; buf[5]=getpid()>>8;
/* TODO make a structure for all this stuff */
/* bytes 4-5 = half-power beam height (uint16) */
/* bytes 6-7 = half-power beam width (uint16) */
/* bytes 8-11 = range in metres, centre beam (uint32) */
/* bytes 16-47 = sender */
/* bytes 48-79 = next hop */
/* bytes 80-83 = latitude (uint32) */
/* bytes 84-87 = longitude (uint32) */
/* bytes 88-89 = X/Z direction (uint16) */
/* bytes 90-91 = Y direction (uint16) */
/* bytes 92-93 = speed in metres per second (uint16) */
/* bytes 94-97 = TX frequency in Hz, uncorrected for doppler (which must be done at the receiving end to take into account
relative motion) */
/* bytes 98-109 = coding method (use for doppler response etc) null terminated string */
/* bytes 110-111 = length of packet body in bytes */
/* bytes 112-127 reserved for future use */
if (len>2048-128) {
WARN("Truncating long packet to fit within 1920 byte limit for dummy interface");
len=2048-128;
}
/* Record length of packet */
buf[110]=len&0xff;
buf[111]=(len>>8)&0xff;
bzero(&buf[128+len],2048-(128+len));
bcopy(bytes,&buf[128],len);
/* This lseek() is unneccessary because the dummy file is opened in O_APPEND mode. It's
only purpose is to find out the offset to print in the DEBUG statement. It is vulnerable
to a race condition with other processes appending to the same file. */
off_t fsize = lseek(interface->alarm.poll.fd, (off_t) 0, SEEK_END);
if (fsize == -1)
return WHY_perror("lseek");
interface->offset = fsize;
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("Write to interface %s at offset=%d", interface->name, interface->offset);
ssize_t nwrite = write(interface->alarm.poll.fd, buf, 2048);
if (nwrite == -1)
return WHY_perror("write");
interface->offset += nwrite;
if (nwrite != 2048)
return WHYF("only wrote %lld of %lld bytes", nwrite, 2048);
return 0;
}
else
{
if(sendto(interface->alarm.poll.fd,
bytes, len, 0, (struct sockaddr *)&s, sizeof(struct sockaddr_in)) != len)
return WHY_perror("sendto(c)");
return 0;
}
}
/* This function is called to return old non-overlay requests back out the
interface they came in. */
int overlay_sendto(struct sockaddr_in *recipientaddr,unsigned char *bytes,int len)
{
if (debug&DEBUG_PACKETTX) DEBUGF("Sending %d bytes",len);
if (overlay_broadcast_ensemble(overlay_last_interface_number,recipientaddr,bytes,len) == -1)
return -1;
return len;
}
/* Register the interface, or update the existing interface registration */
int
overlay_interface_register(char *name,
struct sockaddr_in *local,
struct sockaddr_in *broadcast) {
struct interface_rules *r, *me;
int i;
/* See if the interface is listed in the filter */
me = NULL;
r = interface_filter;
while(r) {
if (!strcasecmp(name, r->namespec))
me = r;
r = r->next;
}
if (me == NULL || me->excludeP) {
if (debug & DEBUG_OVERLAYINTERFACES)
DEBUGF("Interface %s is not interesting.",name);
return 0;
}
/* Search in the exist list of interfaces */
for(i = 0; i < overlay_interface_count; i++)
if (!strcasecmp(overlay_interfaces[i].name, name))
break;
if (i < overlay_interface_count) {
/* We already know about this interface, so just update it. */
/* Check if the broadcast address is the same
TODO: This only applies on Linux because only there can you bind to the bcast addr
DOC 20120608
*/
if ((overlay_interfaces[i].broadcast_address.sin_addr.s_addr & 0xffffffff)
== (broadcast->sin_addr.s_addr & 0xffffffff)) {
/* Same address, mark it as being seen */
overlay_interfaces[i].observed = 1;
return 0;
} else {
if (0) {
/* Interface has changed.
TODO: We should register each address we understand in a list and check them.
DOC 20120608 */
INFOF("Interface changed %08llx.%08llx vs %08llx.%08llx",
/* overlay_interfaces[i].local_address.sin_addr.s_addr */0,
overlay_interfaces[i].broadcast_address.sin_addr.s_addr,
local->sin_addr.s_addr,
broadcast->sin_addr.s_addr);
unwatch(&overlay_interfaces[i].alarm);
close(overlay_interfaces[i].alarm.poll.fd);
overlay_interfaces[i].alarm.poll.fd = -1;
if (overlay_interface_init_socket(i, local, broadcast))
INFOF("Could not reinitialise changed interface %s", name);
}
}
} else {
/* New interface, so register it */
if (overlay_interface_init(name, local, broadcast, me->speed_in_bits, me->port, me->type))
WHYF("Could not initialise newly seen interface %s", name);
else
if (debug & DEBUG_OVERLAYINTERFACES) DEBUGF("Registered interface %s", name);
}
return 0;
}
void overlay_interface_discover(struct sched_ent *alarm){
int no_route, i;
struct interface_rules *r;
struct sockaddr_in dummyaddr;
/* Mark all interfaces as not observed, so that we know if we need to cull any */
for(i = 0; i < overlay_interface_count; i++)
overlay_interfaces[i].observed = 0;
/* Check through for any virtual dummy interfaces */
for (r = interface_filter; r != NULL; r = r->next) {
if (r->namespec[0] != '>')
continue;
for(i = 0; i < overlay_interface_count; i++)
if (!strcasecmp(overlay_interfaces[i].name,r->namespec))
break;
if (i < overlay_interface_count)
/* We already know about this interface, so just update it */
overlay_interfaces[i].observed = 1;
else {
/* New interface, so register it */
if (overlay_interface_init(r->namespec,&dummyaddr,&dummyaddr,
1000000,PORT_DNA,OVERLAY_INTERFACE_WIFI)) {
if (debug & DEBUG_OVERLAYINTERFACES) DEBUGF("Could not initialise newly seen interface %s", r->namespec);
}
else
if (debug & DEBUG_OVERLAYINTERFACES) DEBUGF("Registered interface %s",r->namespec);
}
}
/* Look for real interfaces */
no_route = 1;
#ifdef HAVE_IFADDRS_H
if (no_route != 0)
no_route = doifaddrs();
#endif
#ifdef SIOCGIFCONF
if (no_route != 0)
no_route = lsif();
#endif
#ifdef linux
if (no_route != 0)
no_route = scrapeProcNetRoute();
#endif
if (no_route != 0) {
FATAL("Unable to get any interface information");
}
alarm->alarm = overlay_gettime_ms()+5000;
alarm->deadline = alarm->alarm + 10000;
schedule(alarm);
return;
}
/* remove and free a payload from the queue */
overlay_frame *overlay_queue_remove(overlay_txqueue *queue, overlay_frame *frame){
overlay_frame *prev = frame->prev;
overlay_frame *next = frame->next;
if (prev)
prev->next = next;
else if(frame == queue->first)
queue->first = next;
if (next)
next->prev = prev;
else if(frame == queue->last)
queue->last = prev;
queue->length--;
op_free(frame);
return next;
}
int overlay_queue_dump(overlay_txqueue *q)
{
strbuf b = strbuf_alloca(8192);
struct overlay_frame *f;
strbuf_sprintf(b,"overlay_txqueue @ 0x%p\n",q);
strbuf_sprintf(b," length=%d\n",q->length);
strbuf_sprintf(b," maxLenght=%d\n",q->maxLength);
strbuf_sprintf(b," latencyTarget=%d milli-seconds\n",q->latencyTarget);
strbuf_sprintf(b," first=%p\n",q->first);
f=q->first;
while(f) {
strbuf_sprintf(b," %p: ->next=%p, ->prev=%p\n",
f,f->next,f->prev);
if (f==f->next) {
strbuf_sprintf(b," LOOP!\n"); break;
}
f=f->next;
}
strbuf_sprintf(b," last=%p\n",q->last);
f=q->last;
while(f) {
strbuf_sprintf(b," %p: ->next=%p, ->prev=%p\n",
f,f->next,f->prev);
if (f==f->prev) {
strbuf_sprintf(b," LOOP!\n"); break;
}
f=f->prev;
}
DEBUG(strbuf_str(b));
return 0;
}
int overlay_resolve_next_hop(overlay_frame *frame){
IN();
if (frame->nexthop_address_status==OA_RESOLVED)
RETURN(0);
if (frame->isBroadcast)
bcopy(&frame->destination,&frame->nexthop,SID_SIZE);
else if (overlay_get_nexthop((unsigned char *)frame->destination,frame->nexthop,&frame->nexthop_interface)){
// TODO new code?
frame->nexthop_address_status=OA_UNSUPPORTED;
RETURN(-1);
}
frame->nexthop_address_status=OA_RESOLVED;
RETURN(0);
}
void overlay_init_packet(struct outgoing_packet *packet, int interface){
packet->i = interface;
packet->interface = &overlay_interfaces[packet->i];
packet->buffer=ob_new(packet->interface->mtu);
ob_limitsize(packet->buffer, packet->interface->mtu);
ob_append_bytes(packet->buffer,magic_header,4);
overlay_abbreviate_clear_most_recent_address();
overlay_abbreviate_unset_current_sender();
}
// update the alarm time and return 1 if changed
int overlay_calc_queue_time(overlay_txqueue *queue, overlay_frame *frame){
int ret=0;
long long int send_time;
if (frame->nexthop_address_status==OA_UNINITIALISED)
overlay_resolve_next_hop(frame);
if (frame->nexthop_address_status!=OA_RESOLVED)
return 0;
// when is the next packet from this queue due?
send_time=queue->first->enqueued_at + queue->transmit_delay;
if (next_packet.alarm==0 || send_time < next_packet.alarm){
next_packet.alarm=send_time;
ret = 1;
}
// how long can we wait if the server is busy?
send_time += queue->grace_period;
if (next_packet.deadline==0 || send_time < next_packet.deadline){
next_packet.deadline=send_time;
ret = 1;
}
if (!next_packet.function){
next_packet.function=overlay_send_packet;
send_packet.name="overlay_send_packet";
next_packet.stats=&send_packet;
}
return ret;
}
void overlay_stuff_packet(struct outgoing_packet *packet, overlay_txqueue *queue, long long now){
overlay_frame *frame = queue->first;
// TODO stop when the packet is nearly full?
while(frame){
int drop =0;
frame->isBroadcast = overlay_address_is_broadcast(frame->destination);
if (frame->enqueued_at + queue->latencyTarget < now)
drop=1;
else if(frame->isBroadcast)
drop=overlay_broadcast_drop_check(frame->destination);
if (drop){
DEBUG("Dropping frame due to expiry timeout");
frame = overlay_queue_remove(queue, frame);
continue;
}
if (overlay_resolve_next_hop(frame))
goto skip;
if (!packet->buffer){
// use the interface of the first payload we find
if (frame->isBroadcast){
// find an interface that we haven't broadcast on yet
int i;
for(i=0;i<OVERLAY_MAX_INTERFACES;i++)
{
if (overlay_interfaces[i].observed>0)
if (!frame->broadcast_sent_via[i]){
overlay_init_packet(packet, i);
break;
}
}
if (!packet->buffer){
// oh dear, why is this broadcast still in the queue?
frame = overlay_queue_remove(queue, frame);
continue;
}
}else{
overlay_init_packet(packet, frame->nexthop_interface);
}
}else{
// make sure this payload can be sent via this interface
if (frame->isBroadcast){
if (frame->broadcast_sent_via[packet->i]){
goto skip;
}
}else if(packet->i != frame->nexthop_interface){
goto skip;
}
}
if (overlay_frame_package_fmt1(frame, packet->buffer))
// payload was not queued
goto skip;
// mark the payload as sent
int keep_payload = 0;
if (frame->isBroadcast){
int i;
frame->broadcast_sent_via[packet->i]=1;
// check if there is still a broadcast to be sent
for(i=0;i<OVERLAY_MAX_INTERFACES;i++)
{
if (overlay_interfaces[i].observed>0)
if (!frame->broadcast_sent_via[i]){
keep_payload=1;
break;
}
}
}
if (!keep_payload){
frame = overlay_queue_remove(queue, frame);
continue;
}
skip:
// if we can't send the payload now, check when we should try
overlay_calc_queue_time(queue, frame);
frame = frame->next;
}
}
// fill a packet from our outgoing queues and send it
int overlay_fill_send_packet(struct outgoing_packet *packet, long long now){
int i;
IN();
// while we're looking at queues, work out when to schedule another packet
unschedule(&next_packet);
next_packet.alarm=0;
next_packet.deadline=0;
for (i=0;i<OQ_MAX;i++){
overlay_txqueue *queue=&overlay_tx[i];
overlay_stuff_packet(packet, queue, now);
}
if (next_packet.alarm)
schedule(&next_packet);
if(packet->buffer){
// send the packet
if (packet->buffer->length>=HEADERFIELDS_LEN){
if (debug&DEBUG_PACKETCONSTRUCTION)
dump("assembled packet",&packet->buffer->bytes[0],packet->buffer->length);
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("Sending %d byte packet",packet->buffer->length);
overlay_broadcast_ensemble(packet->i,NULL,packet->buffer->bytes,packet->buffer->length);
}
ob_free(packet->buffer);
overlay_abbreviate_clear_most_recent_address();
RETURN(1);
}
RETURN(0);
}
// when the queue timer elapses, send a packet
void overlay_send_packet(struct sched_ent *alarm){
struct outgoing_packet packet;
bzero(&packet, sizeof(struct outgoing_packet));
overlay_fill_send_packet(&packet, overlay_gettime_ms());
}
// update time for next alarm and reschedule
void overlay_update_queue_schedule(overlay_txqueue *queue, overlay_frame *frame){
if (overlay_calc_queue_time(queue, frame)){
unschedule(&next_packet);
schedule(&next_packet);
}
}
int overlay_tick_interface(int i, long long now)
{
struct outgoing_packet packet;
IN();
if (overlay_interfaces[i].bits_per_second<1) {
/* An interface with no speed budget is for listening only, so doesn't get ticked */
RETURN(0);
}
// initialise the packet buffer
bzero(&packet, sizeof(struct outgoing_packet));
overlay_init_packet(&packet, i);
if (debug&DEBUG_OVERLAYINTERFACES) DEBUGF("Ticking interface #%d",i);
/* 1. Send announcement about ourselves, including one SID that we host if we host more than one SID
(the first SID we host becomes our own identity, saving a little bit of data here).
*/
overlay_add_selfannouncement(i,packet.buffer);
/* Add advertisements for ROUTES */
overlay_route_add_advertisements(packet.buffer);
if (rhizome_enabled() && rhizome_http_server_running())
overlay_rhizome_add_advertisements(i,packet.buffer);
/* Stuff more payloads from queues and send it */
overlay_fill_send_packet(&packet, now);
RETURN(0);
}
long long parse_quantity(char *q)
{
int m;
char units[80];
if (strlen(q)>=80) return WHY("quantity string >=80 characters");
if (sscanf(q,"%d%s",&m,units)==2)
{
if (units[1]) return WHY("Units should be single character");
switch(units[0])
{
case 'k': return m*1000LL;
case 'K': return m*1024LL;
case 'm': return m*1000LL*1000LL;
case 'M': return m*1024LL*1024LL;
case 'g': return m*1000LL*1000LL*1000LL;
case 'G': return m*1024LL*1024LL*1024LL;
default:
return WHY("Illegal unit: should be k,K,m,M,g, or G.");
}
}
if (sscanf(q,"%d",&m)==1)
{
return m;
}
else
{
return WHY("Could not parse quantity");
}
}